I'm not hating on the deal. I think it was a good deal (albeit with some risks) for both teams. Now that I think about it, as crazy as it sounds, I think that dealing Felix Hernandez instead of Pineda might have been a better deal for the Mariners, and probably the Yankees too.
The reason why I say this is because Hernandez salary jumps from $10 million to $18-20 million for the next 3 years. It's highly unlikely in my opinion that Hernandez stays in Seattle after that, so I think that with more time under contract, the better of a package the Mariners can get for Hernandez. I think that his stock can only fall at this point.
Pineda, while obviously unproven and about 3 years younger, has many more years of cheap team control. In addition, the Yankees were said to be offering Montero/Betances/Banuelos and more for King Felix. Add in the fact that the Mariners would have kept Pineda/Campos AND likely gotten another piece from the Yankees (maybe someone like Noesi or a hitting prospect) and I think it looks like a better deal for both teams.
The Mariners shed a lot of payroll and get 3 top prospects with many years of team control (and keep Pineda/Campos) plus their pitcher's ballpark should be kind to Pineda/Betances/Banuelos. Not to mention that the Mariners would have a young core of Montero/Ackley/Smoak and could save a ton of money from the Felix contract to sign someone like Prince Fielder or a cheaper 1B/DH and then add someone like Edwin Jackson. (I'd go for Jackson's youth and durability in Seattle over Oswalt's probably better innings)
Not to mention that the Yankees would have to hire homeless people to squeegee the computers of Yankee fans from all of the misplaced semen that would arise from the Yankees getting King Felix and having a rotation of Sabathia/Felix/Kuroda